In the preparation of finished fabric goods, such as clothing and the like, it is first necessary to unwind cloth from a roll. The unwound cloth is cut into sheets of desired lengths, and such sheets are then superimposed on top of one another to form a stack of cut plies of such material. Thereafter, a suitable pattern may be placed on top of the stack, and the entire stack may be cut en banc according to the pattern to form various individual pieces, which are then sent to subsequent sewing and finishing stations.
The present invention provides an automatic end cutter for use in such cloth spreading and cutting apparatus. One example of a prior art automatic end cutter is shown and described in U.S. Pat. No. 4,779,500, the aggregate disclosure of which is hereby incorporated by reference, and which is assigned to the assignee of the present application. That patent discloses an end cutter in which cloth is unwound from a roll, and is pulled along a cloth spreading table. The patent also shows and describes an automated means for cutting an end length from the unwound cloth. Basically, cloth is first pulled from the roll and is spread upon the table. A cutter is then energized and moved forwardly across the table to sever an end length from the roll. After this length has been cut, the cutter is returned to its initial position. At this point, the cutter and carriage are automatically lifted and lowered to clamp the trailing end of the just-cut length of cloth, and any plies therebeneath. Operators on either side of the table then grasp the free or cut end of the cloth, and pull another length from the roll so as to overlie the previously cut length, and the cutting operation is repeated.
While the device disclosed in the '500 patent does provide a type of automated end cutter, a number of problems have persisted. First, when cloth is pulled from a roll, the unwound length of cloth is put in tension. When released, the advanced length has a tendency to retract or move back toward the roll. Thus, as a practical matter, it is somewhat difficult to accurately position the unwound length at the desired location of the intended cut.
Secondly, the '500 patent discloses a belt-type arrangement for selectively raising the cutter and carriage relative to the table. The carriage and cutter were returned to their lowered position by the force of gravity, amplified by a weight mounted on the distal end of the belt. Thus, the downward clamping force was substantially constant. Upon further reflection and experience, it is felt that it would be desirable to exert a variable downward force on the stack of cut sheets or plies at a controllable down-pressure, in order to more easily accommodate different types of cloth.
Thirdly, the '500 patent did not have a mechanism for stopping the advance of the cutter in the event that cloth "bunched" ahead of the cutter to provide an impediment to the forward motion of the cutter.
Accordingly, it would be generally desirable to provide an improved automatic end cutter incorporating features to solve these problems.